Merge branch 'akpm' (patches from Andrew)

Merge first patchbomb from Andrew Morton:

 - arch/sh updates

 - ocfs2 updates

 - kernel/watchdog feature

 - about half of mm/

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (122 commits)
  Documentation: update arch list in the 'memtest' entry
  Kconfig: memtest: update number of test patterns up to 17
  arm: add support for memtest
  arm64: add support for memtest
  memtest: use phys_addr_t for physical addresses
  mm: move memtest under mm
  mm, hugetlb: abort __get_user_pages if current has been oom killed
  mm, mempool: do not allow atomic resizing
  memcg: print cgroup information when system panics due to panic_on_oom
  mm: numa: remove migrate_ratelimited
  mm: fold arch_randomize_brk into ARCH_HAS_ELF_RANDOMIZE
  mm: split ET_DYN ASLR from mmap ASLR
  s390: redefine randomize_et_dyn for ELF_ET_DYN_BASE
  mm: expose arch_mmap_rnd when available
  s390: standardize mmap_rnd() usage
  powerpc: standardize mmap_rnd() usage
  mips: extract logic for mmap_rnd()
  arm64: standardize mmap_rnd() usage
  x86: standardize mmap_rnd() usage
  arm: factor out mmap ASLR into mmap_rnd
  ...

5 files changed, 90 insertions, 33 deletions

diff --git a/Documentation/cma/debugfs.txt b/Documentation/cma/debugfs.txt
new file mode 100644
index 000000000000..6cef20a8cedc
--- /dev/null
+++ b/Documentation/cma/debugfs.txt
@@ -0,0 +1,21 @@
+The CMA debugfs interface is useful to retrieve basic information out of the
+different CMA areas and to test allocation/release in each of the areas.
+
+Each CMA zone represents a directory under <debugfs>/cma/, indexed by the
+kernel's CMA index. So the first CMA zone would be:
+
+        <debugfs>/cma/cma-0
+
+The structure of the files created under that directory is as follows:
+
+ - [RO] base_pfn: The base PFN (Page Frame Number) of the zone.
+ - [RO] count: Amount of memory in the CMA area.
+ - [RO] order_per_bit: Order of pages represented by one bit.
+ - [RO] bitmap: The bitmap of page states in the zone.
+ - [WO] alloc: Allocate N pages from that CMA area. For example:
+
+        echo 5 > <debugfs>/cma/cma-2/alloc
+
+would try to allocate 5 pages from the cma-2 area.
+
+ - [WO] free: Free N pages from that CMA area, similar to the above.
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 05c36118f8d7..327556349757 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1989,7 +1989,7 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                         seconds.  Use this parameter to check at some
                         other rate.  0 disables periodic checking.
 
-        memtest=        [KNL,X86] Enable memtest
+        memtest=        [KNL,X86,ARM] Enable memtest
                         Format: <integer>
                         default : 0 <disable>
                         Specifies the number of memtest passes to be
@@ -2236,8 +2236,9 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
         nmi_watchdog=   [KNL,BUGS=X86] Debugging features for SMP kernels
                         Format: [panic,][nopanic,][num]
-                        Valid num: 0
+                        Valid num: 0 or 1
                         0 - turn nmi_watchdog off
+                        1 - turn nmi_watchdog on
                         When panic is specified, panic when an NMI watchdog
                         timeout occurs (or 'nopanic' to override the opposite
                         default).
@@ -2322,6 +2323,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                         register save and restore. The kernel will only save
                         legacy floating-point registers on task switch.
 
+        nohugeiomap     [KNL,x86] Disable kernel huge I/O mappings.
+
         noxsave         [BUGS=X86] Disables x86 extended register state save
                         and restore using xsave. The kernel will fallback to
                         enabling legacy floating-point and sse state.
@@ -2464,7 +2467,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 
         nousb           [USB] Disable the USB subsystem
 
-        nowatchdog      [KNL] Disable the lockup detector (NMI watchdog).
+        nowatchdog      [KNL] Disable both lockup detectors, i.e.
+                        soft-lockup and NMI watchdog (hard-lockup).
 
         nowb            [ARM]
 
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index 83ab25660fc9..99d7eb3a1416 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -77,12 +77,14 @@ show up in /proc/sys/kernel:
 - shmmax                      [ sysv ipc ]
 - shmmni
 - softlockup_all_cpu_backtrace
+- soft_watchdog
 - stop-a                      [ SPARC only ]
 - sysrq                       ==> Documentation/sysrq.txt
 - sysctl_writes_strict
 - tainted
 - threads-max
 - unknown_nmi_panic
+- watchdog
 - watchdog_thresh
 - version
 
@@ -417,16 +419,23 @@ successful IPC object allocation.
 
 nmi_watchdog:
 
-Enables/Disables the NMI watchdog on x86 systems. When the value is
-non-zero the NMI watchdog is enabled and will continuously test all
-online cpus to determine whether or not they are still functioning
-properly. Currently, passing "nmi_watchdog=" parameter at boot time is
-required for this function to work.
+This parameter can be used to control the NMI watchdog
+(i.e. the hard lockup detector) on x86 systems.
 
-If LAPIC NMI watchdog method is in use (nmi_watchdog=2 kernel
-parameter), the NMI watchdog shares registers with oprofile. By
-disabling the NMI watchdog, oprofile may have more registers to
-utilize.
+   0 - disable the hard lockup detector
+   1 - enable the hard lockup detector
+
+The hard lockup detector monitors each CPU for its ability to respond to
+timer interrupts. The mechanism utilizes CPU performance counter registers
+that are programmed to generate Non-Maskable Interrupts (NMIs) periodically
+while a CPU is busy. Hence, the alternative name 'NMI watchdog'.
+
+The NMI watchdog is disabled by default if the kernel is running as a guest
+in a KVM virtual machine. This default can be overridden by adding
+
+   nmi_watchdog=1
+
+to the guest kernel command line (see Documentation/kernel-parameters.txt).
 
 ==============================================================
 
@@ -816,6 +825,22 @@ NMI.
 
 ==============================================================
 
+soft_watchdog
+
+This parameter can be used to control the soft lockup detector.
+
+   0 - disable the soft lockup detector
+   1 - enable the soft lockup detector
+
+The soft lockup detector monitors CPUs for threads that are hogging the CPUs
+without rescheduling voluntarily, and thus prevent the 'watchdog/N' threads
+from running. The mechanism depends on the CPUs ability to respond to timer
+interrupts which are needed for the 'watchdog/N' threads to be woken up by
+the watchdog timer function, otherwise the NMI watchdog - if enabled - can
+detect a hard lockup condition.
+
+==============================================================
+
 tainted:
 
 Non-zero if the kernel has been tainted.  Numeric values, which
@@ -858,6 +883,25 @@ example.  If a system hangs up, try pressing the NMI switch.
 
 ==============================================================
 
+watchdog:
+
+This parameter can be used to disable or enable the soft lockup detector
+_and_ the NMI watchdog (i.e. the hard lockup detector) at the same time.
+
+   0 - disable both lockup detectors
+   1 - enable both lockup detectors
+
+The soft lockup detector and the NMI watchdog can also be disabled or
+enabled individually, using the soft_watchdog and nmi_watchdog parameters.
+If the watchdog parameter is read, for example by executing
+
+   cat /proc/sys/kernel/watchdog
+
+the output of this command (0 or 1) shows the logical OR of soft_watchdog
+and nmi_watchdog.
+
+==============================================================
+
 watchdog_thresh:
 
 This value can be used to control the frequency of hrtimer and NMI
diff --git a/Documentation/vm/cleancache.txt b/Documentation/vm/cleancache.txt
index 01d76282444e..e4b49df7a048 100644
--- a/Documentation/vm/cleancache.txt
+++ b/Documentation/vm/cleancache.txt
@@ -28,9 +28,7 @@ IMPLEMENTATION OVERVIEW
 A cleancache "backend" that provides transcendent memory registers itself
 to the kernel's cleancache "frontend" by calling cleancache_register_ops,
 passing a pointer to a cleancache_ops structure with funcs set appropriately.
-Note that cleancache_register_ops returns the previous settings so that
-chaining can be performed if desired. The functions provided must conform to
-certain semantics as follows:
+The functions provided must conform to certain semantics as follows:
 
 Most important, cleancache is "ephemeral".  Pages which are copied into
 cleancache have an indefinite lifetime which is completely unknowable
diff --git a/Documentation/vm/unevictable-lru.txt b/Documentation/vm/unevictable-lru.txt
index 744f82f86c58..86cb4624fc5a 100644
--- a/Documentation/vm/unevictable-lru.txt
+++ b/Documentation/vm/unevictable-lru.txt
@@ -317,7 +317,7 @@ If the VMA passes some filtering as described in "Filtering Special Vmas"
 below, mlock_fixup() will attempt to merge the VMA with its neighbors or split
 off a subset of the VMA if the range does not cover the entire VMA.  Once the
 VMA has been merged or split or neither, mlock_fixup() will call
-__mlock_vma_pages_range() to fault in the pages via get_user_pages() and to
+populate_vma_page_range() to fault in the pages via get_user_pages() and to
 mark the pages as mlocked via mlock_vma_page().
 
 Note that the VMA being mlocked might be mapped with PROT_NONE.  In this case,
@@ -327,7 +327,7 @@ fault path or in vmscan.
 
 Also note that a page returned by get_user_pages() could be truncated or
 migrated out from under us, while we're trying to mlock it.  To detect this,
-__mlock_vma_pages_range() checks page_mapping() after acquiring the page lock.
+populate_vma_page_range() checks page_mapping() after acquiring the page lock.
 If the page is still associated with its mapping, we'll go ahead and call
 mlock_vma_page().  If the mapping is gone, we just unlock the page and move on.
 In the worst case, this will result in a page mapped in a VM_LOCKED VMA
@@ -392,7 +392,7 @@ ignored for munlock.
 
 If the VMA is VM_LOCKED, mlock_fixup() again attempts to merge or split off the
 specified range.  The range is then munlocked via the function
-__mlock_vma_pages_range() - the same function used to mlock a VMA range -
+populate_vma_page_range() - the same function used to mlock a VMA range -
 passing a flag to indicate that munlock() is being performed.
 
 Because the VMA access protections could have been changed to PROT_NONE after
@@ -402,7 +402,7 @@ get_user_pages() was enhanced to accept a flag to ignore the permissions when
 fetching the pages - all of which should be resident as a result of previous
 mlocking.
 
-For munlock(), __mlock_vma_pages_range() unlocks individual pages by calling
+For munlock(), populate_vma_page_range() unlocks individual pages by calling
 munlock_vma_page().  munlock_vma_page() unconditionally clears the PG_mlocked
 flag using TestClearPageMlocked().  As with mlock_vma_page(),
 munlock_vma_page() use the Test*PageMlocked() function to handle the case where
@@ -463,21 +463,11 @@ populate the page table.
 
 To mlock a range of memory under the unevictable/mlock infrastructure, the
 mmap() handler and task address space expansion functions call
-mlock_vma_pages_range() specifying the vma and the address range to mlock.
-mlock_vma_pages_range() filters VMAs like mlock_fixup(), as described above in
-"Filtering Special VMAs".  It will clear the VM_LOCKED flag, which will have
-already been set by the caller, in filtered VMAs.  Thus these VMA's need not be
-visited for munlock when the region is unmapped.
-
-For "normal" VMAs, mlock_vma_pages_range() calls __mlock_vma_pages_range() to
-fault/allocate the pages and mlock them.  Again, like mlock_fixup(),
-mlock_vma_pages_range() downgrades the mmap semaphore to read mode before
-attempting to fault/allocate and mlock the pages and "upgrades" the semaphore
-back to write mode before returning.
-
-The callers of mlock_vma_pages_range() will have already added the memory range
+populate_vma_page_range() specifying the vma and the address range to mlock.
+
+The callers of populate_vma_page_range() will have already added the memory range
 to be mlocked to the task's "locked_vm".  To account for filtered VMAs,
-mlock_vma_pages_range() returns the number of pages NOT mlocked.  All of the
+populate_vma_page_range() returns the number of pages NOT mlocked.  All of the
 callers then subtract a non-negative return value from the task's locked_vm.  A
 negative return value represent an error - for example, from get_user_pages()
 attempting to fault in a VMA with PROT_NONE access.  In this case, we leave the